Verify that Free Countdown Timer is allowed to wake the computer
Learn how to allow your computer to be woken up when it's sleeping by timed events.
1. Open the Control Panel in the Start menu.
2. Open Power Options in the Control Panel.
3. Select Change plan settings next to the active power plan.
4. Select Change advanced power settings.
5. Select Change settings that are currently unavailable in the Power Options window.
6. Set Allow wake timers to Enable under Sleep and then click OK to save the changes.
Note: If the wakeup function still not working properly, try to update BIOS of your computer.
Note: Free Countdown Timer will not wake up your computer when the laptop lid is closed.
Countdown timers and stopwatches, alarm clocks and to-do list, birthday reminders and just about anything you can imagine is readily available.